A black hole that hasn't been heard of since 1989 has suddenly become active again and is now the brightest object in the X-ray sky.
NASA's Cassini spacecraft captures an elegant image of three of Saturn's moons as they glow like delicate slivers in space.
NASA's Cassini spacecraft zooms in on the fractured surface of Dione, one of Saturn's many intriguing moons, and delivers a crater-packed close-up.
Dwarf planet Ceres gets weirder as NASA's Dawn spacecraft gets closer. Check out the latest shots from the cosmic paparazzi.
The permanent, turbulent colossal storms at Saturn's poles are a mystery -- but a new model may explain what causes them.
NASA's Dawn spacecraft cozies up to the fascinating dwarf planet Ceres and sends back the best look yet at its oddball bright spots.
The Phoebe ring takes up as much space as about 7,000 Saturns, most of it pieces of dust smaller than the width of a human hair.
The Mars Reconnaissance Orbiter has found something on Mars that might help in the search for past life on the Red Planet.
Using a series of photos captured by the Dawn spacecraft, along with the addition of a background star field, NASA has created a fun trip around Ceres.
For months now we've been wondering what the bright spots on dwarf planet Ceres are, as seen by the Dawn spacecraft. We've compiled some of our best reader guesses to help you place your bets.